Although Stamets is known for dreaming up new uses for mushrooms, he is also fascinated by their traditional uses, including their role in ancient religious rituals. He’s an avid collector of Mayan “mushroom stones,” small statues crafted in the Pacific highlands of Guatemala between 1000 B.C. and A.D. 900. Anthropologists theorize that these artifacts represent psychedelic mushrooms (possibly psilocybin or Amanita muscaria), which may have been used by shamans to generate mystical states. Many such statues were destroyed by Catholic missionaries during the Spanish conquest; only about 200 are known to survive today. “There’s a really amazing vibe that comes off these stones, especially by firelight,” says Stamets.

Although his passion for mycology was sparked by his own experiences with psilocybin mushrooms as a young man, Stamets no longer advocates casual use of hallucinogens. “I’m conservative when it comes to psychedelics,” he says. “I don’t want to be around people who use them irresponsibly, or who deal them. It just feels unclean. When something is so powerful and sacred, it should be treated with the utmost respect.”